Changes in Gait, Balance and Strength with Aging

The recent article “Age-related changes in gait, balance, and strength parameters: A cross-sectional study” published in PLOS One by Rezaei et al. examines the impact of aging on various physical performance measures such as gait (walking patterns), balance, and muscular strength. The study employs a cross-sectional design, meaning it analyses data collected at one specific point in time across a diverse sample of adults ranging in age, with the objective of understanding how these physical parameters change as people grow older.

Background and Motivation

The motivation behind this study stems from the known correlation between age-related declines in physical abilities and increased risk of falls, decreased independence, and overall diminished quality of life. As gait, balance, and strength are crucial to maintaining mobility and preventing falls, identifying when and how these factors decline can inform interventions that help older adults retain their independence longer. The study also aims to provide insights for clinicians and healthcare professionals to tailor preventative measures and rehabilitation strategies according to age-specific needs.

Methods

The researchers recruited a large group of participants spanning various age groups and used a range of objective measurements to assess gait, balance, and strength. For gait analysis, the study evaluated variables such as walking speed, stride length, and step time variability. Balance was measured through static and dynamic assessments, which included tests for single-leg standing time and balance stability during movement. Strength was assessed primarily through grip strength and lower limb muscle power tests, which are widely accepted indicators of general muscular strength in ageing populations.

Findings

The study found significant age-related declines across all parameters, with notable differences between age groups:

1. Gait: There was a clear trend of reduced walking speed and shorter stride length with increasing age, coupled with an increase in gait variability. These changes often started to manifest in middle-aged adults and progressively worsened in older age groups.
2. Balance: Balance deficits were observed as early as middle age, with a marked reduction in single-leg standing time and stability during dynamic movements in older adults. The results highlight that both static and dynamic balance abilities diminish with age, increasing the risk of falls.
3. Strength: Muscle strength, particularly grip strength and lower limb power, also showed a steady decline with age. This decline was particularly significant in participants over 60 years, indicating that muscle weakness becomes more prominent and impactful in later years.

Interpretation and Implications

The findings suggest that the aging process is associated with measurable declines in gait, balance, and strength, which collectively heighten the risk of falls and mobility impairments. The study highlights that these changes do not occur suddenly but rather develop gradually, implying that early interventions in middle-aged adults could be beneficial. The researchers suggest that routine assessment of gait, balance, and strength could be integrated into clinical practice to detect early declines and support proactive management strategies.

Conclusion

In summary, this cross-sectional study provides valuable insights into how age impacts physical performance parameters crucial for mobility and independence. The age-related deterioration in gait, balance, and strength underlines the importance of early assessment and targeted exercise or rehabilitation interventions aimed at mitigating these declines. By identifying the specific onset of these changes, healthcare providers can better design preventative programs tailored to the needs of ageing adults, thereby potentially enhancing quality of life and reducing the social and economic burdens associated with falls and functional impairments in the elderly population.

This study reinforces the significance of personalised health strategies and preventive measures in addressing the age-related decline in physical function, advocating for policies that encourage physical activity and strength maintenance from a younger age.

Do Ketogenic Diets Trigger Aging?

A new study published in Science Advances has investigated the potential downsides of ketogenic diets. While keto diets are popular for weight loss and some health conditions, this research suggests they may also trigger cellular aging in vital organs.

Key findings of the study:

• Cellular senescence in organs: Mice fed a ketogenic diet showed signs of cellular senescence in multiple organs, including the heart and kidneys. Cellular senescence is basically when cells stop dividing and can contribute to age-related decline.
• Mechanism behind the effect: The study identifies a potential mechanism for this cellular aging. It involves a signalling pathway triggered by AMPK (an enzyme) and caspase-2 (a protein), ultimately leading to increased p53 and p21 proteins, which are linked to cellular senescence.
• Potential implications: The build-up of senescent cells in organs like the heart and kidneys could contribute to inflammation and organ damage. This suggests potential long-term health risks associated with long-term ketogenic diets.
• Possible solutions: The study also offered some hope. They found that interrupting the keto diet with periods of regular eating (intermittent keto) could prevent this cellular senescence. Additionally, there are drugs being developed that target and eliminate senescent cells, which could be a future avenue for mitigating the potential downsides of keto.

Overall, the study highlights the need for a more nuanced understanding of the effects of ketogenic diets. While they may offer benefits, there could also be downsides, particularly with long-term use. As the study was conducted on mice, more research is needed to confirm these findings in humans and explore potential strategies to mitigate any risks.

Can Blood Tests Assess Aging?

A recent study published by Oh, H.SH., Rutledge, J., Nachun, D. et al. in Nature has revealed that the aging of individual organs can be assessed using protein levels in blood plasma. This method, known as plasma proteomics, has been shown to be able to predict mortality and disease risk, and to identify individuals with accelerated aging of specific organs. This finding has the potential to revolutionise our understanding of aging and to develop new therapies for age-related diseases.

The study involved analysing blood plasma samples from over 5,000 individuals from five different cohorts. The researchers developed machine learning models to identify patterns of protein levels that were associated with aging in 11 different organs. These models were then able to predict mortality risk and the risk of developing specific diseases, such as heart failure and Alzheimer’s disease.

The study also found that individuals with accelerated aging of specific organs were more likely to develop age-related diseases. For example, individuals with accelerated heart aging were 250% more likely to develop heart failure, and individuals with accelerated brain and vascular aging were as likely as individuals with high levels of pTau-181 (a biomarker for Alzheimer’s disease) to develop the disease.

These findings have important implications for the development of new therapies for age-related diseases. By measuring the aging of individual organs, doctors may be able to identify individuals at high risk of developing these diseases and to intervene early to prevent them.

Overall, the study provides strong evidence that plasma proteomics is a powerful tool for assessing the aging of individual organs and for predicting mortality and disease risk. This method has the potential to revolutionise our understanding of aging and to develop new therapies for age-related diseases.

Can Aging Be Reversed?

A paper published a few days ago by Yang et al. suggests that aging can be reversed! Here is a summary of the research paper:

• Background: Cellular aging is a complex process that is characterized by a number of changes, including changes in gene expression, DNA methylation, and telomere length. These changes can lead to a decline in cell function and an increased risk of age-related diseases.
• Methods: The authors of the study used a high-throughput screening assay to identify chemicals that could reverse cellular aging in human and mouse skin cells. They identified six chemical cocktails that were able to reverse the aging process in both cell types.
• Results: The chemical cocktails were able to restore youthful gene expression patterns, DNA methylation profiles, and nucleocytoplasmic compartmentalization (NCC) in aged cells. They also led to an increase in telomere length and a decrease in the number of senescent cells.
• Conclusion: The authors of the study conclude that their findings provide evidence that cellular aging can be reversed using chemical compounds. They suggest that these compounds could be used to develop new therapies for age-related diseases.

The study is a significant advance in the field of aging research. It provides new insights into the mechanisms of cellular aging and suggests that it may be possible to reverse the aging process using chemical compounds. This could have major implications for the development of new therapies for age-related diseases.

Here are some of the limitations of the study:

• The study was conducted in cell culture, so it is not yet clear whether the findings will translate to humans.
• The study only looked at a limited number of chemicals, so it is possible that there are other compounds that could also reverse cellular aging.
• The study did not look at the long-term effects of the chemical cocktails, so it is not yet clear whether they are safe for use in humans.

Despite these limitations, the study is a promising step forward in the field of aging research. It provides new hope for the development of new therapies for age-related diseases.

Loving-Kindness Meditation Slows Aging

A recent study by Le Nguyen et al. published in Psychoneuroendocrinology has looked at the effect of loving-kindness meditation on telomore length. Loving-Kindness is a Buddhist meditation that focuses on sending good wishes and kindness to ourselves and others by silently repeating a series of mantras. Telomeres sit at the end of chromosomes and protect the chromosomes from deterioration. Our telomeres gradually shorten over time and this is believed to contribute to aging.

The researchers randomised 142 middle-aged adults into 3 groups: a waiting list control group, a mindfulness meditation group and a loving-kindness meditation group. Telomere length was measured 2 weeks prior to the start and 3 weeks after the end of the 6-week meditation workshop. The results showed that there was significantly less telomere attrition in the loving-kindness meditation group than the control group. The mindfulness meditation group had results that were in between the other 2 groups without being statistically significantly different from either.

We can infer that loving-kindness meditation can slow aging by decreasing the rate at which our telomeres shorten.

Exercise Improves Brain Function

Researchers Art Kramer and Laura Chaddock, from the Beckman Institute at the University of Illinois, have found that children that are aerobically fitter perform better at memory tests than their less fit peers. The improvement in brain function is linked to an increased hippocampal volume. The hippocampus is a structure deep within the brain that is involved with learning and memory. This would suggest that exercise plays a crucial role in the brain development of children.

As we age, there is a natural decline in our mental function. However, studies have shown that this process can be slowed or even reversed! Dr Kirk Erickson conducted a 9 year follow-up study that demonstrated that increased exercise, in the form of walking, was associated with greater grey matter volume and less cognitive impairment. This can have dramatic effects on our ability to lead normal independent lives well into our old age.

The reason for the beneficial influence of exercise on brain growth and function may be due to a protein called Brain-Derived Neurotrophic Factor (BDNF). It supports the survival of existing nerve cells and promotes the growth of new ones and increases the levels of circulating BDNF.

These findings support the promotion of life-long exercise. I guess this sheds new light on the old Roman adage: “a healthy mind in a healthy body”!